The present invention relates generally to a valve actuator for valves having a spring-force operated valve core, according to the preamble portion of claim 1.
A valve connector comprising a valve actuator according to the preamble portion of claim 1 and having an activating pin which is designed as a piston rod of a piston movable in a cylinder and which can move towards a valve under the pressure of liquid and/or gaseous media from a pressure source is well-known from WO-A-96/10903. The conduction channel for conducting pressure media from the cylinder to the coupling section is designed as a central bore of the piston and a radial bore in the piston rod and is controlled by an O-ring of the housing to be open toward the coupling section in the first position of the piston. In the second position of the piston, the passage of the pressure media is inhibited by the O-ring which sealingly cooperates with the piston rod. However, one disadvantage of conventional activating pins is their several tiny parts. The complexity of these conventional activating pins makes production of conventional valve connectors more expensive than necessary.
The valve actuator of the present invention and embodiments thereof are subjects of claim 1 and 2 to 17, respectively. A valve connector and a pressure vessel or hand pump, comprising a valve actuator of the present invention are subjects of claims 18 and 19, respectively. Claim 20 is directed to the use of the valve actuator in a stationary construction.
The present invention provides a valve actuator which comprises an inexpensive combination of a cylinder, within in which the piston driving the activating pin moves, and an activating pin, having a simple construction. This combination can be used in stationary constructions, such as chemical plants, where the activating pin engages the core of a spring force operated valve (e.g. a release valve), as well as in valve connectors (e.g. for inflating vehicle tires). The disadvantage of conventional valve connectors have been overcome by the valve actuator of the present invention. This valve actuator features a piston having a piston ring fitting into the cylinder, where the piston, in its first position, is at a first predetermined distance from the first end of the cylinder. In the piston""s second position, it is at a second predetermined distance from the first end of the cylinder, wherein the second predetermined distance is larger than the first predetermined distance. The cylinder wall comprises a conducting channel for allowing conduction of gaseous and/or liquid media between the cylinder and the coupling section when the piston is in the first position, whereas conduction of gaseous and/or liquid media between the cylinder and the coupling section is inhibited by the piston when the piston is in the second position.
One embodiment of the valve actuator of the present invention according to claim 6 features a conducting channel from the pressure source to the valve to be actuatedthat comprises an enlargement of the cylinder diameter which is arrangend around the piston of the activating pin in the bottom of the cylinder, when the piston is in the first position, enabling the medium from the pressure source to flow to the opened spring-force operated valve, e.g. a Schrader valve. The enlargement of the cylinder""s diameter may be uniform, or the cylinder wall may contain one or several sections near the bottom of the cylinder where the distance between the center line of the cylinder and the cylinder wall increases so that gaseous and/or liquid media can freely flow around the edge of the piston ring when the piston is in the first position. A variant of this embodiment has a valve actuator arrangement of which its cylinder has the enlargement of the diameter twice. The distance between the enlargements can be the same as the distance between the sealing levels of the sealing means. When three valves of different sizes can be coupled the valve actuator may comprise a cylinder with three enlargements. It is however also possible to connect valves of different sizes to a valve actuator having a single arrangement for the enlargement of the diameter of the cylinder. Now therefore the number of enlargements can be different from the number of different valve sizes of valves which can be coupled.
Another embodiment of the present invention according to claim 10 features a conducting channel through a part of the body of the valve actuator. The channel forms a passage for gaseous and/or liquid media between the cylinder and the part of the valve actuator which is coupled to the valve. The orifice of the channel opening in the cylinder is located such that, when the piston is in the first position, pressurized gaseous and/or liquid media flowing from the pressure source to the cylinder may flow further through the channel to the valve to be actuated. When the piston is in the second position, it blocks the cylinder so that the flow of pressurized gaseous and/or liquid media into the channel is not possible.
Instead of air, (mixtures of) gases and/or liquids of any kind can activate the activation pin and can flow around the piston of the valve actuator when the piston is in its first position. The invention can be used in all types of valve connectors to which a spring-force operated core (e.g. a Schrader valve) can be coupled irrespective of the method of coupling or the number of coupling holes in the connector. Furthermore the valve actuator can be coupled to for example a foot pump, car pump, or compressor. The valve actuator can also be integrated in any pressure source (e.g. a handpump or a pressure vessel) irrespective of the availability of a securing means in the valve connector. It is also possible for the invention to be used in permanent constructions where the activating pin of the actuator engages the core of a permanently mounted valve.
The various embodiments described above are provided by way of illustration and should not be constructed to limit the invention. Those skilled in the art will readily recognize various modifications and changes which may be made to the present invention without strictly following the exemplary embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the present invention as claimed.